1. Field of the Disclosure
The embodiments described herein relate to a system and method for re-fracturing select locations, such as prior perforations, prior fractures, and/or prior fracture clusters, of the formation of a multizone horizontal wellbore, also referred to as a high angle wellbore, hereinafter referred to as a horizontal wellbore. The formation may also re-fracture the formation through a sliding sleeve left open during a prior hydraulic fracturing process.
2. Description of the Related Art
Natural resources such as gas and oil may be recovered from subterranean formations using well-known techniques. For example, a horizontal wellbore may be drilled within the subterranean formation. After formation of the horizontal wellbore, a string of pipe, e.g., casing, may be run or cemented into the well bore. Hydrocarbons may then be produced from the horizontal wellbore.
In an attempt to increase the production of hydrocarbons from the wellbore, the casing may be perforated and fracturing fluid may be pumped into the wellbore to fracture the subterranean formation. The fracturing fluid is pumped into the well bore at a rate and a pressure sufficient to form fractures that extend into the subterranean formation, providing additional pathways through which fluids being produced can flow into the well bores. The fracturing fluid typically includes particulate matter known as a proppant, e.g., graded sand, bauxite, or resin coated sand, may be suspended in the fracturing fluid. The proppant becomes deposited into the fractures and thus holds the fractures open after the pressure exerted on the fracturing fluid has been released.
Another method to increase the production of hydrocarbons from a horizontal wellbore is to attempt to fracture the formation through ported collars or tubulars within the horizontal wellbore. Typically, these ported collars may be selectively closed by a sliding sleeve, which may be actuated to an open position by various means such as by the use of a shifting tool or by the application of a pressure differential. Once the port is opened, fracturing fluid may be pumped down the well and out the port in an attempt to fracture the formation to increase production of hydrocarbons.
A production zone within a wellbore may have been previously fractured, but the prior fracturing may not have adequately fractured the formation leading to inadequate production from the production zone. Even if the formation was adequately fractured, the production zone may no longer be producing at adequate levels. Over an extended period of time, the production from a previously fractured horizontal wellbore may decrease below a minimum threshold level. One technique in attempting to increase the hydrocarbon production from the wellbore is the addition of new fractures within the subterranean formation. One potential problem in introducing new fractures in the formation is that fracturing fluid pumped into the wellbore may enter prior fractures formed in the subterranean formation instead of creating new fractures. Expandable tubulars or cladding procedures have been used within a wellbore in an attempt to block the flow path of the fracturing fluid to the old fractures, instead promote the formation of new fracture clusters. The use of expandable tubulars or cladding may not adequately provide the desired results and further, may incur too much expense in the effort to increase products from the wellbore. A more efficient way to increase the production of a horizontal wellbore may be needed.